INTRODUCTION

eta/DYNAFORM Version 5.7.1 software is an LS-DYNA-based sheet metal forming simulation solution package developed by Engineering Technology Associates, Inc. The specialty CAE software combines the analysis power of LS-DYNA Versions 971 with the streamlined pre- and post-processor functions. These analysis codes and interactive functions are uniquely integrated to service the sheet metal forming industry in tooling design and development. The program also maximizes traditional CAE techniques to reduce prototyping costs and lead time for product development.

 

eta/DYNAFORM’s analysis engine is LS-DYNA, which is developed and currently supported by the Livermore Software Technology Corporation (LSTC) of Livermore, California. It is a general purpose, non-linear, dynamic, finite element analysis code utilizing explicit and implicit capabilities for solving fluid and solid structural problems. The code has been developed for applications such as automobile crashworthiness, occupant safety, underwater explosion, and sheet metal forming.

 

The bottleneck of the metal forming development cycle is the hard tooling design lead-time. The eta/DYNAFORM CAE approach simulates this tooling process and thereby reduces the tooling tryout time and the associated cost for producing high quality stamped parts. eta/DYNAFORM effectively simulates the four major design concerns in the tooling process: Binder Wrap, Draw Die, Spring Back, and Multiple Stage Tooling. These simulations enable engineers to conduct feasibility studies of a product design early in the design cycle.

 

eta/DYNAFORM features well-defined tooling surface data to predict the performance of a stamping for areas such as tearing, wrinkling, and thinning, in addition to predicting skid mark and spring back effects.

 

Availability:

eta/DYNAFORM is available for all UNIX workstation platforms including DEC(Alpha), HP, IBM, SUN, and SGI.  It is available on PC for Windows and NT operating systems of 1998 and above. For LINUX, the Red Hat version 7.2 and above is supported.

 

Special features of eta/DYNAFORM Version 5.7 include:

 

A process oriented module- AUTOSETUP

The multi stage simulation setup in AUTOSETUP module provides a complete scheme for solving stamping problems and allows the user to set up line die simulation. This module is process oriented and enables user to easily set up all types of simulation.

 

AUTOSETUP allows the user to define stamping direction, forming simulation of tailor welded blanks, hydroforming simulation, multi stage simulation and trimming operation. In addition, Superplastic forming simulation and thermal forming simulation are added to this module. The enhanced material library in Auto Setup module allows the user to add the standard material library for corporations to the program interface for easier selection of common used materials. The major improvements include:

 

SCP module

Springback Compensation Process (SCP) is used for die compensation of sprung sheet metal parts. Springback is one of the crucial issues for sheet stamping industry. The springback compensation based on finite element technology is utilized to alleviate the severity of springback phenomena. SCP is used to modify the original die face with the springback quantity generated from springback simulation to make the part dimension to fall within the tolerance of intended part design after springback. The eta/DYNAFORM also provides some practical tools for the user to repair the compensated die face and improve the efficiency for die face design.

 

Die System AnalysisDSA

The Die System Analysis module provides a series of solutions for solving the problems encountered in the practical production. The Finite Element Analysis is utilized to efficiently predict the possible problems in die design and within the die production line to optimize the design of die structure and production line. This could greatly reduce the try-out time and lower the development cost of new products. The Die System Analysis module includes Die Structural Integrity (DSI), Scrap Shedding Removal (SSR) and Sheet Metal Transferring Handling (SMTH). In all the analysis of DSA module, the program provides simple graphic interfaces to guide the user to execute complicated preparation and simulation processes.   

 

Update Drawbead function

The Drawbead function has been greatly improved in eta/DYNAFORM 5.7. This module contains Line Bead and Geometry Bead, which can be easily converted to each other. In eta/DYNAFORM 5.7, the GUI of Line Bead and operation style is overhauled to facilitate easy drawbead definition and modification. The user may define the drawbead curve through selection, import and creation and define the lock force of drawbead by using three methods. One of the methods is to calculate drawbead force according to section shape, which is very convenient, and the defined section shape is relating to the geometry bead. The line bead can be imported and exported. All operations in drawbead generation, including property definition, create, edit and restrain force definition, can be easily performed without advanced training. Geometry bead is utilized to create geometry bead mesh according to the defined section shape. It automatically reads in the information of line bead for the creation of geometry mesh model. The user may also import curve directly to define geometry bead. The high quality surfaces will also be generated when generating mesh model.

 

More functional DFE module

Compared to the previous version, many functions in the DFE module of eta/DYNAFORM 5.7 are improved and added to satisfy the needs of the friendly and functional operation. The user can quickly import the product and complete the entire process of die face design. The major improvement includes:

 

 

Enhanced BSE module

In eta/DYNAFORM 5.7, QUICK UNFOLD, BATCH MSTEP and BATCH BSE modules are added for the user to perform quick batch operations on multiple parts and output reports. MSTEP is improved to estimate forming capabilities during the part design stage while obtaining the outline. The trim line module is improved to obtain the trim line of complicated parts quickly. The nesting function has also been improved and optimized to satisfy the needs of the friendly and functional operation. For nesting of complicated parts, the nesting result yields higher material utilization rate and more practical nesting pattern.

 

Rotary Draw Bending

Rotary Draw Bending is a Quick Setup module for tube bending analysis. The module is equipped with user-friendly and process oriented GUI. Furthermore, the module enables users to easily tube bending model.

 

Enhanced Pre-processor functions

 

Support LS-DYNA 971 R3.2.1

The input file created by eta/DYNAFORM 5.7 supports LS-DYNA 971 (47756 version) format. The eta/DYNAFORM User’s Manual describes functions of the software interface. For further details about solver, please refer to the LS-DYNA User’s Manual published by the LSTC.

 

Documentation

A Training Manual is available to assist first time users with the general operating procedures of the program. The manual includes a relatively simple demonstration of a draw die simulation of an S-channel. The step-by-step procedure guides users through the complete process and flow of tasks.  A new user can usually complete the training program and be ready to begin a production project in less than two hours.

The Applications Manual discusses the basics of the sheet metal forming process and transmits some fundamental knowledge of tooling design and related topics to the user.  The following are typical examples of simulations that are included to demonstrate eta/DYNAFORM’s capabilities, features, and functions:

 

Case 1.  NUMISHEET’2002 Fender Draw Simulation

Case 2.  Double Action of Solid Element Simulation

Case 3.  Springback and Springback Compensation simulation

Case 4.  Tube Bending and Hydroforming Simulation

 

These workshop examples enable users to fully understand general pre- and post-processing operations in addition to the applications of binder wrap simulation, draw bead force calculation, draw die simulation, Forming Limit Diagram (FLD), thickness, thinning, wrinkling, and springback simulation.